1. Field
Embodiments described herein relate to Positron Emission Tomography (PET) and Single Photon Emission Computer Tomography (SPECT).
2. Background
In Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT), a fixture is used routinely to accurately position a radioactive phantom (e.g., point source, line source, cylinder source, etc.) in the scanner's imaging field-of-view (FOV) to fulfill certain calibration or performance measurements. In some cases, the patient support assembly/bed is required to be out of the scanner's FOV during measurement. This fixture is attached to the patient bed or stands directly on the floor, and is used to hold the phantom in the required position with respect to the scanner FOV.
A PET/SPECT normalization apparatus has been proposed to emulate a plane source by moving a line source across the scanner's transverse or axial FOV. A three-dimensional (3D) positioning robot has been proposed to position a point source precisely along (x, y, z) axes in the PET scanner FOV for point-spread-function (PSF) measurement to improve PET image resolution.
Other measurements (e.g., time-of-flight timing calibration, NEMA resolution and sensitivity measurement) also require a fixture to position a point source or a line source in a precise location within the FOV.
Typically, separate fixtures are designed to hold different phantoms for different calibration and performance measurements. For example, the fixture that holds the scanning line source is different from the fixture that holds the stationary point source for PSF measurement.